Gmail can be accessed by Outlook or Outlook express since it has an IMAP and authenticated SMTP setup.
You can't tell Excel to use Gmail - it doesn't work like that. It just starts a new email in your mail client and the mail client takes it from there... The problem is possibly that Excel can only use Microsoft email clients when using the builtin in "send to email" function.
If you want to use this a lot, you could set up Outlook Express to use your Gmail account (at least for sending only).
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Christian
#40104192 120Gb (no longer in my E36 M3, won't fit the E46 M3)